Nonreturn valve



Feb. 3. w25. LSZSAS F2. MCFARLAN NONRETURN VALVE Filed Jan. 5, 1921 2 Sheets-Sheet l 'Illlfl-llf t' Feb 3. M25. 1,525,405

R. MCFARLAN NONRETURN VALVE Y Filed Jan. 5, 3921 2 Sheets-Sheet 2 Patented Feb. 3, 1925.

NITE!) STATES PATENT oFFlcE.

RANDALL MCFARLAN,

OF GINCINNAT, O'HIO.

NONRETUB-N VALVE.

Application led January 3, 1921.

T0 all whom t may concern.'

Be it known that I, RANDALL MCFARLAN, a citizen ot' the United States of America, and resident of Cincinnati, in the county of Hamilton and State ot' Ohio, have invented a new and useful mprovement in a Nonreturn Valve, of which the following is a specification.

This invention relates to the class of valves which are interposed between each boiler of a series of boilers and the main steam line, and which are provided with two seats, against one of which the valve is seated in case there is no pressure in the boiler, and against the other of which the valve is seated in case of any break in the main steam line.

In valves of this class heretofore in use, there has been a tendency Jfor the valve to chatter, particularly when the main steam line supplies a reciprocating engine. In such instances the non-return valve does not become thoroughly raised 'rom its seat and therefore upon each closing oit of the steam the valve returns to its seat, to be raised again when the flow of steam takes place.

rlfhe object of the present invention is to provide a means for insuring a full rising of the non-return valve from its seat and to maintain it in that position whilst there is pressure in its boiler, or until it is carried to the opposite seat by a break in the main steam line.

Another object is to provide a simple and efficient device of the type referred to.

These and other objects are attained by the means described herein and disclosed in the accompanying drawing in which Fig. 1 is a plan view of a valve, embodying my invention parts being broken away.

Fig. 2 is an enlarged section view on line 2-2 of Fig. l.

Fig. 3 is a sectional view on line 3 3 ot Fig. 4.

Fig. 4; is a sectional view on line 4-4 of Fig. 3.

Fig. 5 is a sectional view on line 5-5 of Fig. 3.

My invention comprises a housing A within which is mounted a valve B adapted to control the flow of a fluid, such as steam, trom the boiler C and a valve governor D or a steam locking cylinder.

The housing A is adapted to be mounted upon the boiler C so that the chambers therein will communicate with the interior Serin no. 434,494.

of the boiler C. rlhe housing A is preferably made of a head section a and a bodyy section a, adapted to be mounted upon one another by any suitable means such as bolts a2. A secondary valve seat a3 is mounted intermediate the chamber a# formed within the head of the housing and the secondari7 chamber a5 formed within the body of the housing. A primary valve seat 0; is mounted within the body a" ot' the housing, intermediate the primary chamber a7 formed therein and the secondary chamber a5. A reciprocating stem a9 is mounted upon the housing and extends thereinto. The outer end of the stem at) is threaded and engages a threaded bearing @12 mounted upon the housing A. A handle a is mounted upon the exterior end of the stem a9 whereby the stem 0,9 may be rotated and thereby be reciprocated longitudinally in and out of the housing A so as to seat the valve B upon the primary valve seat CLG.

The compound valve disk B is recipro- -cally mounted within the secondary chamber a5 of the housing by means or' the primary valve stem I) extending from one side of the valve B. The primary valve stem is reciprocally mounted upon a spider as extending from the valve seat at. The secondary valve stem extends from theopposite side of the valve B and extends thru the secondary valve seat as and into vthe chamber at within the head of the housing.

The secondary valve stem t has a centralr bore b2 into which extends the inner end of the reciprocating stem a. The secondary valve stem is adapted to reciprocate longitudinally upon the stem 0,9. The compound valve disk B has formed on one ot' its sides a primary valve b3 adapted to engage the' primary valve seat a, and upon its opposite side a secondary valve bt adapted to engage the secondary valve seat a?. Mounted upon the secondary valve stem 1) is a collar b5 having the pins ZJ extending therefrom upon which are mounted the roller bearings 67.

The valve B is controlled governor D. This governor by the valve mechanism comprises a plunger casing Z mounted uponv housing A and having withinit a plunger chamber d communicating with the primary chamber a7 means of a duct d2. Contained within the chamber d is a plunger cl3, one end of which extends from t-he casing` 0l and has mounted upon it a roller d4. A

revoluble shaft (i5 is mounted uponrthehousw ing A and extends thru the head thereof. Upon the outer end of the revoluble shaft di is mounted a cam rlin alignment with the roller d* on the plunger' d3. The cam has two lobes ZM and (ZU) between which is formed a detent die. The shaft CZ is secured against lateral displacement by forming `a shoulder (Z7 thereon engaging the bearing 68 mounted upon the housing A. Suit-- ablepackingd9 is mounted about the shat't d5 by means of a gland d10. Mounted upon the shaft Z5 interiorly of the chamber aL is an arm d having a yolred12 termed .thereon, the ingers Z13 thereof engaging the roller bearing 97 mounted upon the secondary stemt. 'Rotation of the plunger is avoidedvbyianysuitable means such as the longitudinal slot d in casing Z and the pin dlg mounted on the plunger and extending into slot d, A shoulder d1 is formed upon. the inner wall oi the phinger casing Z so as to project into the plunger chamber KZ; The plunger Z3 has a shoulder d20 intermediate iftslength adapted to engage the shoulder X19 formed on the casing cl, thereby limiting the movement or the plunger`l and the 4contact of *the said two shoulders providing a steam proof connection augmenting the packing rings 21 mounted upon the plungen The shoulders prevent the pressure of the steam within the plunger chamberfrom moving the plunger toward and upon the shaft Z5 so as to cause damage toV any Vof theparts that might-.be injured by an uncontrolled movement of the plunger.

The operation of my device is as follows:

We will assume that the steanrs being generated. within the boiler C. in' this position, assuming that the valve B had been moved upon the primary valve seat a by mean-s of the stem cg, by gravity, or by the pressure of thesteam in the mainsteam line and that the stem a /has then been moved to a position as shown in Fig. .1, thelplungenwill be retained upon the base of 'chamber CZ by the lobe d engaging the? roller d4; or `by gravity. The. steaml generated :withinithe boiler (l will enter the chamber'd" thru the duct (12. lVhen the pressure of the Vsteam within the boiler equalizes'that of the steam within-the main steamflline, the pressurezot the steam within theboiler `vvill push-the `plunger (Z3 toward the revoluble shaft (Z5, and the movement ot the valve B will be occasioned by the rotationof the shaft (Z5, the roller (Z4 onthev plunger moving over the tace of the lobe d, on the cam d0. These movements are all relativeand simultaneous and will con tinue until the :roller d* yregisters with the detentffll, which registration will retain the valve B in a position intermediate'with: the primary and secondary valve'seats. Slight 'fluctuations of the relative pressures withinthe boiler and the mainsteam lineiwill be insufficient to move `the"rolle`r from the detent, wherefore the rattling and chattering reiierred to before l1s eliminated.

Should a break occur in the main steam line, the steam within the boiler will cause the secondary valve upon B to engage its seat at, thereby shutting ott communication of the boiler C and the main steam line. This movement ot' the valve B causes the shaft (Z5 to rotate and the roller leaves the detent and moves over the lobe (ZM on thexcam ZG and the plunger cl3 is moved downward in the chamber cl. `When the pressures have been substantially.equalizeth the pressure 'ot the steam upon the plunger (Z3 causes'the plunger (Z3 to again assume the position shown in Fig. 2 andl thereby checks the valve B as Vit moves toward the seat'a and prevents chattering oi" the valve B. blight fluctuations ot steam pressures tending to move the valve between the two valve seats a3 and a, resulting from the use of boilers. with reciprocating engines and the like will 'not ai'ect the valve B to such an extent aslto reciprocate the valve between its seats and thereby the chattering and the wear `resulting therefrom is eliminated.

What l cla-im is:

l. The combination of a housing enclosing oppositely-t'acing valve-seats,VA a double- 'faced valve adapted to reciprocate Vbetween said seats, a valve-stem'adapted -to forcibly seat -the valve against one of said seats.r a valve-controlling'device embodying a cylinderin communication with the supply-side ot the housing, a piston working insaid cylinder having a rod extending outthrough the cylinder, and means co-acting with'said rod to positively actuate said valve.

2. 1n a nonreturn valve mechanism, a housing, two oppositely-tacing valve seats enclosed therein, a double-faced valve working between said seats,.a manually operable valve stem iior seatingthe valve against the valve scat adj acenta supply source vand adapted to be adjusted. to permit the valve to seat itself against the other seat, and means tor holding the valve intermediate the seats while fluid is passing'throughthe'housing tromthe supply-source, saidmeans em'- bodying a rock-shaft. `extending into the housing' and connected to the valve in such' manner as to reciprocate the valveA relatively as the rock-shaft is actuated and fluid-.actu` ated means operative"upon'the'outer end of theroclr-shatt and having constant connection with the supplyisource oi' fluid.r

3.Y In a non-return .valve the combination ot a housing, comprising a head and a body, a chamber within the head adapted to com municate with a mainline, a primary and a secondary chamber .within thebody, the primary chamber beingfadapt-ed to-communicate with a. boiler, a primary valve seat intermedia-te the primary and secondary chamber, a valve seat intermediate the chamber in the head and the secondary chamber, a valve Within the secondary chamber adapted to engage the valve seats, a valve stem, a revoluble shaft extending into the housing, and arm mounted on the shaft and pivotally engaging the valve stem, a plunger casing, a plunger chamber .within the casing communicating with the primary chamber, and a plunger within the plunger chamber and adapted to control the movement of the revoluble shaft.

Ll. In a non-return valve the combination of a housing, comprising a head and body, a chamber within the head adapted to communicate with a main line, a primary anda secondary chamber within the body, the primary chamber being adapted to communicate with a boiler, a primary valve seat intreinediate the primary and secondary chambers, a valve seat intermediate the chamber in the head and the secondary chamber, a valve within the secondary chamber adapted to engage the Valve seats, a valve stem, a revoluble shaft extending into the housing, an arm mounted on the shaft and pivotally engaging the valve stem, a plunger casing, a plunger chamber within the casing communicating with the primary chamber, a plunger within the chamber, a roller on the plunger, and a cam mounted on the revoluble shaft and engaging the roller.

In a non-return valve the combination of a housing, comprising a head and a body, a chamber within the head adapted to communicate with a main line, a primary and a secondary chamber within the body, the primary chamber being adapted to communicate with a boiler, a'primary valve seat intermediate the primary and secondary chamber, a valve seat intermediate the (-haniber in the head and the secondary chamber, a valve within the secondary chamber adapted to engage the valve seats, a valve stem, a collar mounted on the stem, pins mounted on the collar, a revo-luble shaft extending into the housing, an arm on the revoluble shaft, a yoke on the arm, fingers on the yoke engaging the pins, a cam on the shaft, a plunger casing, a plunger chamber within the casing communicating with the primary chamber, and a plunger in the plunger chamber and engaging the cam.

6. In a non-return valve the combination of a housing, comprising a head and a body, a chamber Within the head adapted to communicate with a main line, a primary and a secondary chamber within the body, the primary Chamber being adapted to communicate with a boiler, a primary valve seat intermediate the primary and secondary chambers, a valve seat intermediate the chamber in the head and the secondary chamber, a valve within the secondary chamber adapted to engage the valve seats, a valve stem, a revoluble shaft extending into the housing, an arm mounted on the shaft and pivotally engaging the valve stem, a cam mounted on the shaft, lobes on the cam and a detent formed between the lobes, a plunger casing, a plunger chamber within the casing communicating with the primary chamber, a plunger in the plunger chamber adapted to engage a lobe when one of the valves is closed and to engage in the detent when the valves are open.

7. In a non-return valve mechanism. a housing enclosing two oppositely-facing valve-seats, a double-faced valve working between said seats, a manually-operable valvestem for seating the valve against the valveseat adjacent the supply-source and adapted to be adjusted to permit the valve to seat itself against the other seat, and Huid-actuated means for holding the valve intermediate the seats while the fluid is passing through the housing from the supply-source, said means embodying a piston under constant pressure from the supply-source, a rock-shaft extending into the housing and having positive connection with the valve, and means co-acting between said piston and said rook-shaft for constantly tending to hold the valve in a position intermediate said valve-seats.

In testimony whereof, I have hereunto subscribed my name this 22nd day of December, 1920.

RANDALL MCFARLAN. 

